Alternator Noise Revisited

[GalinHdz]

I had to use three filters to completely eliminate the alternator noise in my airplane. I went from cheapest to most expensive as I worked on the problem.

1 - At the actual alternator. It lowered the noise a little
Alternator Capacitor

2 - At the firewall directly from the alternator before the main bus. This dropped the noise even more but not completely and I want no noise whatsoever.
Ameri-King AK-950-FTR

3 - Just filters power to the audio panel. With this the noise is completely gone. As quiet as my car.
Smoothie Brickwall Filter

I hope you don't need this much cleaning up.

[dilamipo]

Originally Posted by GalinHdz

I had to use three filters to completely eliminate the alternator noise in my airplane. I went from cheapest to most expensive as I worked on the problem.

1 - At the actual alternator. It lowered the noise a little Alternator Capacitor

2 - At the firewall directly from the alternator before the main bus. This dropped the noise even more but not completely and I want no noise whatsoever Ameri-King AK-950-FTR

3 - Just filters power to the audio panel. With this the noise is completely gone. As quiet as my car. Smoothie Brickwall Filter

I hope you don't need this much cleaning up.

thank you GalinHdz,
what kind of alternator you have on your RV?
I have the van's 60amp.

Dimitri

[GalinHdz]

Originally Posted by dilamipo

thank you GalinHdz,
what kind of alternator you have on your RV?
I have the van's 60amp.

Dimitri

I have a 70A ESI 32B19549 "aftermarket" alternator. It isn't on an RV but on a fiberglass KIS4. Fiberglass aircraft tend to have more issues with electrical noise than aluminum ones do. I had an RV-9A and it did not have any noise issues.

[RV6airplanePilot]

Originally Posted by GalinHdz

I had to use three filters to completely eliminate the alternator noise in my airplane. I went from cheapest to most expensive as I worked on the problem.

1 - At the actual alternator. It lowered the noise a little
Alternator Capacitor

2 - At the firewall directly from the alternator before the main bus. This dropped the noise even more but not completely and I want no noise whatsoever.
Ameri-King AK-950-FTR

3 - Just filters power to the audio panel. With this the noise is completely gone. As quiet as my car.
Smoothie Brickwall Filter

I hope you don't need this much cleaning up.

So I ordered a smoothie, the inventor has died, but his company still sells them. My strange noise may not come from the alternator, but I used the smoothie to power the main com radio and audio panel. Results were perfect; noise is gone. Thanks for telling me about it.

[Neal@F14]

For simple alternator "whine" noise... a cheap choke and capacitor (LC filter) type of alternator noise filter inserted into the power feed to the radios and intercom will often do the job perfectly fine for a bargain price.

Radio Shack used to sell these for about $10 for use with car stereos and CB radios but they haven't stocked them for a few years. You can find them online or in car stereo shops.

Here's one here: http://www.sonicelectronix.com/item_...C-CSS-100.html